Method oe forming coupling ends on drill-tube sections



P. BOYD AND A. M. SAUNDERS;

METHOD OF FORMING COUPLING ENDS 0N DRILL IUBE SECTIONS.

APPLICATION FILED MAY25. 191s.

1 325,073 Patented Dec. 16, 1919.

2 SHEETS-SHEET 1.

INVENTOH PETER'BOYD. /4.M.5/lU/VUE/?S. BY

Fg4. I

P. BOYD AND A. M. SAUNDERS.

METHOD OF FORMING C'OUPLING ENDS 0N DRILL TUBE SECTIONS.

APPLICATION FILED MAY 25. 191B.

1 25,073 Patented Dec. 16, 1919.

2 SHEETS-SHEET 2.

IIVVENTOR PfTf/I BOYD. 1 M. $AU/VDER5 ATTO may NITEDs TEs PATENT OFFICE.

PETER BOYD, OF BEAVER, AND AUGUSTUS M. SAUNDERS, OF MCKEESPORT, PENNSYL- VANIA, ASSIGNORS TO NATIONAL TUBE COMPANY, VANIA, A. CORPORATION OF NEW JERSEY.

OF PITTSBURGH, PENNSYL- METHOD OF FORMING COUPLING ENDS ON DRILL-TUPE SECTIONS.

Specification of Letters Patent.

. Patented Dec. 1c, 1919.

Application filed May 25, 191a. Serial No. 236,577.

To all @ukom it may concern: 2 Be 1t known that we, PETER BOYD and AuGUsrUs M. SAUNDERS, citizens of the United States, residing at Beaver, Beaver method for forming integral coupling ends on'the ends of welded or seamless tubes of the class used for core drills and shot drills. Heretofore' it has beencustomary to 1011). the ends of such tube sections by means 'of detachable unions or other fittings, which in unsatisfactory because continued use of the sometimes reaching a length of threethousand feet, and the. extra weight due to the in creased thickness of the wall of a drill tub'e of such length-would make the use of such tubes prohibitive, such a drill tube naturally being a great deal more expensive tomanufacture and requiring greater power to operate.

By the utilization of our method-rwe are able to increase the thickness-of the wall of the drill. tube at the ends thereof to give sufficient metal for the formation of an integral coupling without adding materiallyto the weight of the tube section.

Our invention'is illustrated by the accompanying drawings in which Fi re'l and Fig. 2are respectively a lon gitu a1 section and an end elevation show ingthe uniform wall thickness and-the relative diameter and wall thickness of a tube before being subjected to any of the steps of our method.

Figs. 3 toll inclusive" are longitudinal sections on any axialv line of the tube illustrating the various successive steps in our improved method of upsetting or thicken-. ing the tube wall at the ends of the drill tube of Figs. 1 and 2.

Fig. 12 is a longitudinal .section of the male endof the drill tube after the upsetting operations have been completed to the extent shown in Fig. 11.

Fig. 13 illustrates the condition of the tube after being swaged to form a tapered end thereon in forging the male end of the .tube. practice has been found-to be more or less Fig. 14 shows the completed male end of the drill tube with a screw thread cut on the tapered eiid.

Fig. 15 is a section on the line 1515 of Fig, 14.-.

Fig. 16 is a longitudinal section of the female end of a drill tube which has been upset in a similar manner to that illustrated in Figs. 3-to 11, inclusive. l a

Fig. 17 illustrates the finished form of the female end of the drill section showing the internal threads formed therein.

\ Fig. 18 is a sectional view on line 18'18 of Fig. 17.

In carrying out our method, the end of a tube, made by the lapweld, seamless or other approved process, after first being heated, is lnserted in a die having a diameter the same as that of the exterior of the tube, the axes of the die and tube coinciding. The heated tube end is then subjected to endwise of the upsetting press slightly increasing the thickness of the walls of the tube as shown in Figs. 4 and 5, and the metal being displaced inwardly due-to the restraining action of the surrounding outer die. The upsetting operation is repeated several times, the result, as shownin Figs. 5, 6, 7, and 8, being to materially shorten the thickness in ess the tube wall at the end thereof by di-slplllac-- ing the metal inwardly, the wall thic pressure by an upsetting press, the action the diameter at the end of the die is sli htly.

reater than the outside diameter the ill tube. We then Subject the end of the tube to another series, of operatlons wh1ch action expands the end of the tube, offsetting the thickened wall thereof outwardly as in- I dicated in Fig. 9, whereupon we again'subject the end of the tube to another series of lengthwise compressing or upsetting op: erations which causes the metal of the tu e wall to be so displaced that it fills the enlarged cavity A of the die as shown in Figs. 10 and 11.

fter thecom of our method t e end of the tube will formed up to the shape illustrated in Fig. 12, and we then submit the end of the tube to a swagin operation to form the tapered end B and t e shoulder G thereon. A-suitable tool is then employed to form the screw threads D on the tapered end C thereof wlich completes themale end of the drill tu e. I The method of forming or upsetting the female end of the tube is substantially the-- same as that above described with the exception that the tapered end B is not swaged thereon, the interior threads E being cut on' the inner wall of the tube to coact with the threads I) on the mating end of an adjacent drill section.

We are aware that. it .is not generically" new to perform simple upsetting operations upon tubular work, but it is our belief that such olperations have never before been successfu has been done by the method herein disclosed. We. also believe that "it is novel to v first increase .the thickness of the walls of the tube by displacing the metal inwardly and then ofi'settin the thickened wall as de-.

scribed, to form a ub on the tube. The continual working of the metal increases its fiber strength thus making a tougher end on the drill tube at the point at which-the excessive strains are usually felt in core drills and the like. With a drill tube thus. formed, as the threads of the coacting coupling members become worn ,through' continued use, the threads can be recut and the'shoulder G of the hubbe cut back as indicated in dotted'lines in Fig. 14.

Similarly the interior threads E may. also 'be" recut when they become badly worn, the

wallsat the end of the tube in each case beletion ofthe above ste s y carried to such a great extent as and then machining ing sufliciently thick permit of several 66 recutting operations before the tube will have to. be finally discarded.

Though we'have described in considerable detail the various steps in carrying out our method, it is obvious that slightly difi'erent steps may be employed or the sequenceof operations somewhat changed by those skilled in the art without departing from.

' Ward in said successive upsetting operations and then further shortening the tube and increasing the wall thiclmess of the thickened d in a second series ofsmall and successive operations and forcing the displaced metal radially outward in at least part of said second series of upsetting operations.

2. The method of forming hubs. on tubes which consists in shortening the tube and materially increasing its wall thiclmess adjacent to an end of the tube in a series of small and successive upsetting. operations and forcing the displaced metal radially inward in sa1d successive upsetting operations and then further shortening the tube and in-. creasing the wall thickness of the thickened end in a second series of small and successive operations and forcing the displaced metal radially outward in at least part of said second series of upsetting operatlons and then swagingthe thickened tube end to further shape the hub ofthe tube and, thereby provide a tapered end thereon. v

. 3. The method of forming hubs on tubes which consists in shortening the tube and materially increasing its wall thicknessadjacent to an end of the tube in a series of small and successive upsetting operations and forcing the displaced metal radially inward in sa1d successive upsetting operations and thenlfurther shortening the tube and increasing the wall thickness of the thickened end in a second series of small and successive operations and forcing the displaced metal radially outwardin at least part of said second series of upsetting operations screw threads thereon.

4. The method of forming hubs on tubes which consists in shorteningthe tube and materially increasing its wall thickness adsmall and successive upsetting operations and forcing'the displaced metal radially inward in sa1d successive upsetting operations and then further shortening the tube and inthehub and cutting -jacent to an end of the tube in a series of creasing the Wall thickness of the thickened end in a second series of small and successive operations and forcing the displaced metal radially outward in at least part of said second series of upsetting operations and then swaging the thickened tube end to further shape the hub of the tube and thereby provide a tapered end thereon and then machining the hub and cutting screw threads thereon.

In Witness whereof, We have hereunto signed our names.

PETER BOYD. AUGUSTUS M. SAUNDERS. 

